Abstract

Mobiscope is a discovery service where clients submit longrunning queries to continually find sets of moving network resources within a specified area. As in moving object databases (MODBMSs), moving resources advertise their positions as functions over time. When Mobiscope receives a query, it runs the query statically against advertisements (ads) that are currently cached by Mobiscope, and then continuously over ads that Mobiscope receives subsequently. For scalability, Mobiscope distributes the workload to multiple nodes by spatial coordinates. Application-level routing protocols based on geography ensure that all queries find all matching resources on any node without significant processing overhead. Simulation results indicate that Mobiscope scales well, even under workloads that stress Mobiscope’s distribution model.

Franklin and Denny have been partially supported by the NSF under grants IIS- 0086057 and SI-0122599, by an IBM Faculty PartnershipA ward, and by research funds from Intel, Microsoft, and the UC Micro program.